1. Field of the Invention
Exemplary embodiments of the present invention relate to a display device and a manufacturing method thereof.
2. Description of the Background
A liquid crystal display (LCD) is one of the most commonly used flat panel displays. An LCD may include two substrates with electrodes formed on the substrates, and a liquid crystal layer interposed between the two substrates. In the LCD, a voltage is applied to the electrodes to realign liquid crystal molecules of the liquid crystal layer to thereby regulate transmittance of light passing through the liquid crystal layer.
LCD structures with field generating electrodes formed on two display panels are widely used. A plurality of pixel electrodes and thin film transistors may be arranged in a matrix format on one of the display panels (hereinafter referred to as a thin film transistor array panel). Color filters of red, green, and blue, and a light blocking member are formed on the other display panel (hereinafter referred to as a common electrode panel). A common electrode may cover the entire surface of the common electrode panel.
However, in the above-described LCD structures, the pixel electrodes and the color filters are disposed on different display panels such that it is difficult to align the pixel electrodes and the color filters with each other. Accordingly, an alignment error may occur.
To solve this problem, a color filter on array (COA) structure in which the pixel electrodes and the color filters are formed on the same display panel is provided.
When forming the color filters along with the thin film transistor, the color filter may be formed by an Inkjet printing method. In the Inkjet printing method, liquid ink is sprayed (jetted) to predetermined divided portions to implement an ink-colored filter, and a plurality of colors including red, green, and blue can be simultaneously formed, such that the manufacturing process, time, and cost can be considerably reduced.
Liquid ink is used in the Inkjet printing. Thus partitions to enclose the ink may be required; however, the partitions may be formed improperly due to particles in a light exposer or poor adhesion with the substrate. If the partition is lost or has a small height, the liquid ink may pass through the lost part or over the partition such that colors of the neighboring pixels may be mixed.
Also, if the height of the partition is large, a step may be generated by a portion where the ink is not filled, and protrusions and depressions of a passivation layer may be formed due to the step such that a process margin for a light blocking member and a photosensitive film is reduced.
In addition, the thickness of the color filter may be different from the edge of the color filter to the central part thereof in one pixel. Accordingly, the color may be different between the central part of the color filter and the edge of the color filter, thereby decreasing the color reproducibility.
The above information disclosed in this BACKGROUND section is only for enhancement of understanding of the background of the invention and therefore may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.